Driver assistance functions based on ultrasonic sensors are sufficiently familiar from the related art. Parking spaces are identified using ultrasonic sensors and offered to the driver as parking possibility. A semi-automated or fully automated parking assistance system aids the driver when pulling into the free parking space thus identified. It is likewise known to transmit the positions and dimensions of detected parking spaces to a data server. See, for example, DE 10 2004 062 021 A1, DE 10 2009 028 024 A1, and DE 10 2008 028 550.
In the case of existing systems, the false detection rate for detecting parking spaces is relatively high. Thus, parking spaces can be detected as the result of reflections off of trees or walls, for example, without a real parking space being present physically.
DE 10 2013 018 721 A1 describes a method for detecting at least one parking space using a sensor that sends out a primary signal and receives an echo signal. Objects are classified using the method, differentiation being made between vehicle and non-vehicle, for example. The recognition of curbstones, trees, trash cans, and the like is also possible. Likewise, it is possible to differentiate between stationary and non-stationary objects. In addition, it is provided to determine the orientation of the recognized objects. Parking spaces with high probability are located between two objects classified as vehicle, with sufficient distance between the two objects. using an object recognized as automobile whose orientation was determined, the alignment of the parking space can also be identified.
DE 10 2011 113 916 A1 relates to a method to classify parking scenarios for a parking system. In that case, objects delimiting a parking space, depth of the parking space, width of the parking space, and further parameters are used. The parking scenarios are assessed by evaluating the individual criteria of each parking scenario, the individual evaluations of each classification of each parking scenario being combined. In this context, the assessment or classification can be carried out on the basis of an assignment of probabilities or by a distribution of point values.
DE 10 2014 009 627 A1 describes a method for reporting a free parking space for a vehicle. In that case, free parking spaces are detected using in-vehicle sensors and provided with attributes such as length, width, height, angle, type, and geographic position. In addition, a link to a digital roadmap is also possible, in order to rule out the use of areas that are too close to an intersection, for example. The parking spaces detected are filtered on the basis of the ascertained information. Relevant parking spaces are reported to other vehicles, either a direct communication between two vehicles or a central data server being used for that purpose.